Am planning a surprise trip for my elderly parents to Switzerland for 4 days. They will be in Lucerne for the first two days, and will most probably be in Zurich for the next two, for ease of flying out again. Unfortunately I will not be able to accompany them due to last minute work commitments. I was thus wondering if you might have any recommendations as to where they might enjoy going and, given that they don't speak/understand much English and no German at all, and have limited mobility (my mum has a bad leg) would find it easiest to navigate. (The 'candidates' I have for now are the zurich zoo, botanical gardens, and the old town)
Alternatively, would you suggest that Geneva might be a better place instead?
Thank you in advance!